1. Field of the Invention
The present invention generally relates to an apparatus to facilitate accurate transfer of one or multiple points on one surface to one or multiple points on another surface, and a method therefor. The apparatus is in the form of a mobile structure including a base supported by four wheels and a movable top member or plate which can be leveled to facilitate use on uneven surfaces. Multiple lasers mounted on the mobile structure are used to transfer multiple points from the floor to an overhead surface, such as a ceiling of a room, hallway or the like, as well as from wall to wall.
More particularly, the mobile apparatus and method of the present invention are especially useful in marking the points on an overhead surface, such as ceilings of a building relative to a reference line on the floor surface. The apparatus serves to locate target points where support brackets or hangers are to be placed for the hanging of ductwork of an overhead air handling duct system or cable trays, piping or other conduit systems to be hung from a ceiling by tracking a reference line or markings on the floor. A linear measuring device indicates linear spacing for the support brackets on the ceiling to position the bracket attachments points in accurate lateral and linear relationship to the ductwork or other system to be installed.
2. Description of the Prior Art
One of the difficult problems in building construction and renovation is the proper placement of the support brackets or hangers from the ceiling which are used to support HVAC ductwork, cable trays, water piping, or other overhead conduit systems. Often this placement is a xe2x80x9chit or missxe2x80x9d operation, using plumb lines, measuring tapes and the like to best estimate the target points by reference to a centerline of the applicable duct, cable, piping or other system on the floor surface. The task is even more difficult for the installing contractor if the ceiling surface is uneven or certain components have been already installed, e.g. the HVAC ductwork is already installed when trying to target hanger attachment points for cable trays, piping and the like. There is presently no available apparatus which can accurately mark the desired target points on the ceiling from a centerline of the proposed system on the floor surface.
Further, a laser or lasers have been utilized to determine or indicate the relationship between various points or reference lines in space including determining the relationship between vertically spaced reference points on one surface to a target point or points on another surface or surfaces. However, the prior art does not disclose a mobile or wheeled structure supporting multiple lasers which simultaneously emit beams in multiple directions to transfer multiple points from one surface to another surface or surfaces, such as from the floor to the ceiling as well as wall to wall. Also, the prior art does not disclose a mobile apparatus and method to indicate the location of hanger brackets on the ceiling to support ducts in an air duct system by utilizing a reference duct system center line on the floor surface of a building. The prior art also fails to disclose a mobile apparatus having pointers thereon relating to a reference center line on a floor surface underlying the apparatus with a tracking system indicating spatial relationship from point to point along the reference center line. The prior art also fails to disclose an attachment to support a laser for rotation about a vertical axis to assist with curved installations.
The present invention includes a mobile apparatus having a base supported by wheels to enable it to be moved along a supporting surface, such as a floor surface of a building floor being, built out or under renovation. The base includes a movable top member or plate which can be leveled and provides support for two fixed laser brackets to accommodate single point layout as well as two laser brackets affixed at the ends of transversely movable support arms to facilitate dual point layout. A drum with a 360xc2x0 protractor on its upper end has a rotatable laser bracket to enable movement of a laser beam in a horizontal plane about a generally vertical axis. The lasers for the present invention are preferably conventional self-leveling lasers which emit a beam in five directions, three in the horizontal plane and two in the vertical plane.
The base of the mobile apparatus also includes a vertical pointer extending downwardly from the center of the front and rear of the base in order to center the cart directly over a chalk line, or other reference line or markings, on the floor surface in order to properly orient the apparatus in relation to the chalk or reference line or markings. In addition, the mobile apparatus includes a fifth laser which provides a laser beam that can be moved about a radius having a center coinciding with the center of a protractor on the upper surface of a cylindrical drum mounted on the leveled movable top member or plate. A tracking system in the form of a resettable linear measurement device accurately measures linear spacing from point to point on the reference line or surface markings in order to properly indicate linear spacing of points on the overhead surface. The apparatus also preferably includes a handle for easy manipulation.
The method of the present invention contemplates tracking a reference line or markings on the floor surface of a building floor being built out or under renovation with a mobile apparatus. At appropriate intervals, vertical laser beams from conventional lasers properly positioned on the mobile apparatus identify target locations on the overhead ceiling or surface of the subject building floor where support brackets or hangers should be attached for supporting HVAC ductwork, cable trays, piping and other overhead conduit systems. The appropriate intervals are determined by a resettable linear measurement device mounted on the mobile apparatus to accurately measure linear spacing from point to point on the reference line or markings in order to properly indicate linear spacing of points on the overhead ceiling or surface. A laser also provided on the mobile apparatus can track selected locations on wall surfaces to further identify target locations on the overhead ceiling.
In accordance with the foregoing, it is an object of the present invention to provide an apparatus and method to facilitate the transfer of one or multiple points on one surface of a structure to a single or multiple points on another surface with a high degree of, accuracy and which can be easily and quickly adjusted to accurately transfer such point or points.
A further object of the present invention is to provide an apparatus and method which can accurately pinpoint target points on an overhead surface for attaching support brackets or hangers for HVAC ductwork, cable trays, piping and other overhead conduit systems based upon a chalk or reference line or markings laid out on a floor surface.
Another object of the present invention is to provide an apparatus having a wheeled base in the form of a frame supported adjacent its forward and rear edges by support wheels at each side and a handle structure upstanding from the rear to facilitate manipulation in the form of a pushcart, with the base supporting a top member or plate vertically above the base and which can be leveled in relation to the base to facilitate use of the apparatus on uneven surfaces.
Still a further object of the present invention is to provide a mobile apparatus in accordance with the preceding objects in which the top member includes two fixed spaced laser brackets to accommodate single point layout and a pair of adjustable support arms with laser brackets thereon to facilitate dual point layout.
Still another object of the present invention is to provide a mobile apparatus in accordance with the preceding objects which includes a linear measurement device having an indicator adjacent the handle structure for observation by an operator using the apparatus to enable accurate measurement of the linear distance moved by the apparatus and accurate spacing of linear spaced points without the points being marked along a reference line with which front and rear pointers on the cart are associated.
Yet a further object of the present invention is to provide an apparatus in accordance with the preceding objects in which the top member or plate of the apparatus is provided with a detachably mounted drum having a 360xc2x0 protractor on an upwardly facing surface. A pivot arm mounted on the drum supports a laser for rotation in a horizontal plane about the pivot point of the pivot arm. The laser can also rotate in a vertical plane. The pivot arm can be locked in a desired position which can be determined by pointers associated with the 360xc2x0 protractor to enable a laser beam to indicate arcuate or curved lines on a surface. The drum also includes peripheral openings to enable the laser beam from another laser supported on the top member to shine through the openings in the drum to indicate a point forwardly of the apparatus.
Yet another object of this invention is to provide a mobile apparatus in accordance with the preceding objects which will conform to conventional forms of manufacture, be of simple construction and easy to use so as to provide an apparatus that will be economically feasible, long lasting and relatively trouble free in operation.
Still yet another object of the present invention to be specifically enumerated herein is to provide a mobile apparatus and method in accordance with the preceding objects which can track a reference line or markings on the floor surface of a building floor and can identify target locations on the overhead ceiling by vertical laser beams from lasers properly positioned on the mobile apparatus.